As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK DUE TO THE CAPTAIN'S AIRSPEED INDICATION AT ZERO ON TAKE OFF, ALONG WITH RUDDER RATIO, AILERON LOCKOUT, IAS DISAGREE FAULTS. FOUND PITOT LINE TO LEFT ADC NOT CONNECTED. CONNECTED PITOT LINE AND PERFORMED A LEAK CHECK OF SYSTEM. ALL CHECKED NORMAL.